Search results for: nuclear fusion
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1348

Search results for: nuclear fusion

868 PbLi Activation Due to Corrosion Products in WCLL BB (EU-DEMO) and Its Impact on Reactor Design and Recycling

Authors: Nicole Virgili, Marco Utili

Abstract:

The design of the Breeding Blanket in Tokamak fusion energy systems has to guarantee sufficient availability in addition to its functions, that are, tritium breeding self-sufficiency, power extraction and shielding (the magnets and the VV). All these function in the presence of extremely harsh operating conditions in terms of heat flux and neutron dose as well as chemical environment of the coolant and breeder that challenge structural materials (structural resistance and corrosion resistance). The movement and activation of fluids from the BB to the Ex-vessel components in a fusion power plant have an important radiological consideration because flowing material can carry radioactivity to safety-critical areas. This includes gamma-ray emission from activated fluid and activated corrosion products, and secondary activation resulting from neutron emission, with implication for the safety of maintenance personnel and damage to electrical and electronic equipment. In addition to the PbLi breeder activation, it is important to evaluate the contribution due to the activated corrosion products (ACPs) dissolved in the lead-lithium eutectic alloy, at different concentration levels. Therefore, the purpose of the study project is to evaluate the PbLi activity utilizing the FISPACT II inventory code. Emphasis is given on how the design of the EU-DEMO WCLL, and potential recycling of the breeder material will be impacted by the activation of PbLi and the associated active corrosion products (ACPs). For this scope the following Computational Tools, Data and Geometry have been considered: • Neutron source: EU-DEMO neutron flux < 1014/cm2/s • Neutron flux distribution in equatorial breeding blanket module (BBM) #13 in the WCLL BB outboard central zone, which is the most activated zone, with the aim to introduce a conservative component utilizing MNCP6. • The recommended geometry model: 2017 EU DEMO CAD model. • Blanket Module Material Specifications (Composition) • Activation calculations for different ACP concentration levels in the PbLi breeder, with a given chemistry in stationary equilibrium conditions, using FISPACT II code. Results suggest that there should be a waiting time of about 10 years from the shut-down (SD) to be able to safely manipulate the PbLi for recycling operations with simple shielding requirements. The dose rate is mainly given by the PbLi and the ACP concentration (x1 or x 100) does not shift the result. In conclusion, the results show that there is no impact on PbLi activation due to ACPs levels.

Keywords: activation, corrosion products, recycling, WCLL BB., PbLi

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867 Fatigue Crack Growth Rate Measurement by Means of Classic Method and Acoustic Emission

Authors: V. Mentl, V. Koula, P. Mazal, J. Volák

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Nowadays, the acoustic emission is a widely recognized method of material damage investigation, mainly in cases of cracks initiation and growth observation and evaluation. This is highly important in structures, e.g. pressure vessels, large steam turbine rotors etc., applied both in classic and nuclear power plants. Nevertheless, the acoustic emission signals must be correlated with the real crack progress to be able to evaluate the cracks and their growth by this non-destructive technique alone in real situations and to reach reliable results when the assessment of the structures' safety and reliability is performed and also when the remaining lifetime should be evaluated. The main aim of this study was to propose a methodology for evaluation of the early manifestations of the fatigue cracks and their growth and thus to quantify the material damage by acoustic emission parameters. Specimens made of several steels used in the power producing industry were subjected to fatigue loading in the low- and high-cycle regimes. This study presents results of the crack growth rate measurement obtained by the classic compliance change method and the acoustic emission signal analysis. The experiments were realized in cooperation between laboratories of Brno University of Technology and West Bohemia University in Pilsen within the solution of the project of the Czech Ministry of Industry and Commerce: "A diagnostic complex for the detection of pressure media and material defects in pressure components of nuclear and classic power plants" and the project “New Technologies for Mechanical Engineering”.

Keywords: fatigue, crack growth rate, acoustic emission, material damage

Procedia PDF Downloads 371
866 Numerical Investigation of Solid Subcooling on a Low Melting Point Metal in Latent Thermal Energy Storage Systems Based on Flat Slab Configuration

Authors: Cleyton S. Stampa

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This paper addresses the perspectives of using low melting point metals (LMPMs) as phase change materials (PCMs) in latent thermal energy storage (LTES) units, through a numerical approach. This is a new class of PCMs that has been one of the most prospective alternatives to be considered in LTES, due to these materials present high thermal conductivity and elevated heat of fusion, per unit volume. The chosen type of LTES consists of several horizontal parallel slabs filled with PCM. The heat transfer fluid (HTF) circulates through the channel formed between each two consecutive slabs on a laminar regime through forced convection. The study deals with the LTES charging process (heat-storing) by using pure gallium as PCM, and it considers heat conduction in the solid phase during melting driven by natural convection in the melt. The transient heat transfer problem is analyzed in one arbitrary slab under the influence of the HTF. The mathematical model to simulate the isothermal phase change is based on a volume-averaged enthalpy method, which is successfully verified by comparing its predictions with experimental data from works available in the pertinent literature. Regarding the convective heat transfer problem in the HTF, it is assumed that the flow is thermally developing, whereas the velocity profile is already fully developed. The study aims to learn about the effect of the solid subcooling in the melting rate through comparisons with the melting process of the solid in which it starts to melt from its fusion temperature. In order to best understand this effect in a metallic compound, as it is the case of pure gallium, the study also evaluates under the same conditions established for the gallium, the melting process of commercial paraffin wax (organic compound) and of the calcium chloride hexahydrate (CaCl₂ 6H₂O-inorganic compound). In the present work, it is adopted the best options that have been established by several researchers in their parametric studies with respect to this type of LTES, which lead to high values of thermal efficiency. To do so, concerning with the geometric aspects, one considers a gap of the channel formed by two consecutive slabs, thickness and length of the slab. About the HTF, one considers the type of fluid, the mass flow rate, and inlet temperature.

Keywords: flat slab, heat storing, pure metal, solid subcooling

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865 Conception of a Reliable Low Cost, Autonomous Explorative Hovercraft 1

Authors: A. Brand, S. Burgalat, E. Chastel, M. Jumeline, L. Teilhac

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The paper presents actual benefits and drawbacks of a multidirectional Hovercraft conceived with limited resources and designed for indoor exploration. Recent developments in the field have led to apparition of very powerful automotive systems capable of very high calculation and exploration in complex unknown environments. They usually propose very complex algorithms, high precision/cost sensors and sometimes have heavy calculation consumption with complex data fusion. Those systems are usually powerful but have a certain price and the benefits may not be worth the cost, especially considering their hardware limitations and their power consumption. Present approach is to build a compromise between cost, power consumption and results preciseness.

Keywords: Hovercraft, indoor exploration, autonomous, multidirectional, wireless control

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864 Conception of a Reliable Low Cost and Autonomous Explorative Hovercraft

Authors: S. Burgalat, L. Teilhac, A. Brand, E. Chastel, M. Jumeline

Abstract:

The paper presents actual benefits and drawbacks of a multidirectional autonomous hovercraft conceived with limited resources and designed for indoor exploration. Recent developments in the field have led to the apparition of very powerful automotive systems capable of very high calculation and exploration in complex unknown environments. They usually propose very complex algorithms, high precision/cost sensors and sometimes have heavy calculation consumption with complex data fusion. These systems are usually powerful but have a certain price, and the benefits may not be worth the cost, especially considering their hardware limitations and their power consumption. The present approach is to build a compromise between cost, power consumption and results preciseness.

Keywords: hovercraft, indoor exploration, autonomous, multidirectional, wireless control

Procedia PDF Downloads 278
863 Investigation on the Acoustical Transmission Path of Additive Printed Metals

Authors: Raphael Rehmet, Armin Lohrengel, Prof Dr-Ing

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In terms of making machines more silent and convenient, it is necessary to analyze the transmission path of mechanical vibrations and structure-bone noise. A typical solution for the elimination of structure-bone noise would be to simply add stiffeners or additional masses to change the transmission behavior and, thereby, avoid the propagation of vibrations. Another solution could be to use materials with a different damping behavior, such as elastomers, to isolate the machine dynamically. This research approach investigates the damping behavior of additive printed components made from structural steel or titanium, which have been manufactured in the “Laser Powder Bed Fusion“-process. By using the design flexibility which this process comes with, it will be investigated how a local impedance difference will affect the transmission behavior of the specimens.

Keywords: 3D-printed, acoustics, dynamics, impedance

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862 Numerical Simulation of Two-Phase Flows Using a Pressure-Based Solver

Authors: Lei Zhang, Jean-Michel Ghidaglia, Anela Kumbaro

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This work focuses on numerical simulation of two-phase flows based on the bi-fluid six-equation model widely used in many industrial areas, such as nuclear power plant safety analysis. A pressure-based numerical method is adopted in our studies due to the fact that in two-phase flows, it is common to have a large range of Mach numbers because of the mixture of liquid and gas, and density-based solvers experience stiffness problems as well as a loss of accuracy when approaching the low Mach number limit. This work extends the semi-implicit pressure solver in the nuclear component CUPID code, where the governing equations are solved on unstructured grids with co-located variables to accommodate complicated geometries. A conservative version of the solver is developed in order to capture exactly the shock in one-phase flows, and is extended to two-phase situations. An inter-facial pressure term is added to the bi-fluid model to make the system hyperbolic and to establish a well-posed mathematical problem that will allow us to obtain convergent solutions with refined meshes. The ability of the numerical method to treat phase appearance and disappearance as well as the behavior of the scheme at low Mach numbers will be demonstrated through several numerical results. Finally, inter-facial mass and heat transfer models are included to deal with situations when mass and energy transfer between phases is important, and associated industrial numerical benchmarks with tabulated EOS (equations of state) for fluids are performed.

Keywords: two-phase flows, numerical simulation, bi-fluid model, unstructured grids, phase appearance and disappearance

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861 Development of Alpha Spectroscopy Method with Solid State Nuclear Track Detector Using Aluminium Thin Films

Authors: Nidal Dwaikat

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This work presents the development of alpha spectroscopy method with Solid-state nuclear track detectors using aluminum thin films. The resolution of this method is high, and it is able to discriminate between alpha particles at different incident energy. It can measure the exact number of alpha particles at specific energy without needing a calibration of alpha track diameter versus alpha energy. This method was tested by using Cf-252 alpha standard source at energies 5.11 Mev, 3.86 MeV and 2.7 MeV, which produced by the variation of detector -standard source distance. On front side, two detectors were covered with two Aluminum thin films and the third detector was kept uncovered. The thickness of Aluminum thin films was selected carefully (using SRIM 2013) such that one of the films will block the lower two alpha particles (3.86 MeV and 2.7 MeV) and the alpha particles at higher energy (5.11 Mev) can penetrate the film and reach the detector’s surface. The second thin film will block alpha particles at lower energy of 2.7 MeV and allow alpha particles at higher two energies (5.11 Mev and 3.86 MeV) to penetrate and produce tracks. For uncovered detector, alpha particles at three different energies can produce tracks on it. For quality assurance and accuracy, the detectors were mounted on thick enough copper substrates to block exposure from the backside. The tracks on the first detector are due to alpha particles at energy of 5.11 MeV. The difference between the tracks number on the first detector and the tracks number on the second detector is due to alpha particles at energy of 3.8 MeV. Finally, by subtracting the tracks number on the second detector from the tracks number on the third detector (uncovered), we can find the tracks number due to alpha particles at energy 2.7 MeV. After knowing the efficiency calibration factor, we can exactly calculate the activity of standard source.

Keywords: aluminium thin film, alpha particles, copper substrate, CR-39 detector

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860 Hepatic Regenerative Capacity after Acetaminophen-Induced Liver Injury in Mouse Model

Authors: N. F. Hamid, A. Kipar, J. Stewart, D. J. Antoine, B. K. Park, D. P. Williams

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Acetaminophen (APAP) is a widely used analgesic that is safe at therapeutic doses. The mouse model of APAP has been extensively used for studies on pathogenesis and intervention of drug induced liver injury based on the CytP450 mediated formation of N-acetyl-p-benzo-quinoneimine and, more recently, as model for mechanism based biomarkers. Delay of the fasted CD1 mice to rebound to the basal level of hepatic GSH compare to fed mice is reported in this study. Histologically, 15 hours fasted mice prior to APAP treatment leading to overall more intense cell loss with no evidence of apoptosis as compared to non-fasted mice, where the apoptotic cells were clearly seen on cleaved caspase-3 immunostaining. After 15 hours post APAP administration, hepatocytes underwent stage of recovery with evidence of mitotic figures in fed mice and return to completely no histological difference to control at 24 hours. On the contrary, the evidence of ongoing cells damage and inflammatory cells infiltration are still present on fasted mice until the end of the study. To further measure the regenerative capacity of the hepatocytes, the inflammatory mediators of cytokines that involved in the progression or regression of the toxicity like TNF-α and IL-6 in liver and spleen using RT-qPCR were also included. Yet, quantification of proliferating cell nuclear antigen (PCNA) has demonstrated the time for hepatic regenerative in fasted is longer than that to fed mice. Together, these data would probably confirm that fasting prior to APAP treatment does not only modulate liver injury, but could have further effects to delay subsequent regeneration of the hepatocytes.

Keywords: acetaminophen, liver, proliferating cell nuclear antigen, regeneration, apoptosis

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859 Analysis of Nonlinear and Non-Stationary Signal to Extract the Features Using Hilbert Huang Transform

Authors: A. N. Paithane, D. S. Bormane, S. D. Shirbahadurkar

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It has been seen that emotion recognition is an important research topic in the field of Human and computer interface. A novel technique for Feature Extraction (FE) has been presented here, further a new method has been used for human emotion recognition which is based on HHT method. This method is feasible for analyzing the nonlinear and non-stationary signals. Each signal has been decomposed into the IMF using the EMD. These functions are used to extract the features using fission and fusion process. The decomposition technique which we adopt is a new technique for adaptively decomposing signals. In this perspective, we have reported here potential usefulness of EMD based techniques.We evaluated the algorithm on Augsburg University Database; the manually annotated database.

Keywords: intrinsic mode function (IMF), Hilbert-Huang transform (HHT), empirical mode decomposition (EMD), emotion detection, electrocardiogram (ECG)

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858 Cognition of Driving Context for Driving Assistance

Authors: Manolo Dulva Hina, Clement Thierry, Assia Soukane, Amar Ramdane-Cherif

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In this paper, we presented our innovative way of determining the driving context for a driving assistance system. We invoke the fusion of all parameters that describe the context of the environment, the vehicle and the driver to obtain the driving context. We created a training set that stores driving situation patterns and from which the system consults to determine the driving situation. A machine-learning algorithm predicts the driving situation. The driving situation is an input to the fission process that yields the action that must be implemented when the driver needs to be informed or assisted from the given the driving situation. The action may be directed towards the driver, the vehicle or both. This is an ongoing work whose goal is to offer an alternative driving assistance system for safe driving, green driving and comfortable driving. Here, ontologies are used for knowledge representation.

Keywords: cognitive driving, intelligent transportation system, multimodal system, ontology, machine learning

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857 Face Recognition Using Discrete Orthogonal Hahn Moments

Authors: Fatima Akhmedova, Simon Liao

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One of the most critical decision points in the design of a face recognition system is the choice of an appropriate face representation. Effective feature descriptors are expected to convey sufficient, invariant and non-redundant facial information. In this work, we propose a set of Hahn moments as a new approach for feature description. Hahn moments have been widely used in image analysis due to their invariance, non-redundancy and the ability to extract features either globally and locally. To assess the applicability of Hahn moments to Face Recognition we conduct two experiments on the Olivetti Research Laboratory (ORL) database and University of Notre-Dame (UND) X1 biometric collection. Fusion of the global features along with the features from local facial regions are used as an input for the conventional k-NN classifier. The method reaches an accuracy of 93% of correctly recognized subjects for the ORL database and 94% for the UND database.

Keywords: face recognition, Hahn moments, recognition-by-parts, time-lapse

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856 Corrosion Protection and Failure Mechanism of ZrO₂ Coating on Zirconium Alloy Zry-4 under Varied LiOH Concentrations in Lithiated Water at 360°C and 18.5 MPa

Authors: Guanyu Jiang, Donghai Xu, Huanteng Liu

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After the Fukushima-Daiichi accident, the development of accident tolerant fuel cladding materials to improve reactor safety has become a hot topic in the field of nuclear industry. ZrO₂ has a satisfactory neutron economy and can guarantee the fission chain reaction process, which enables it to be a promising coating for zirconium alloy cladding. Maintaining a good corrosion resistance in primary coolant loop during normal operations of Pressurized Water Reactors is a prerequisite for ZrO₂ as a protective coating on zirconium alloy cladding. Research on the corrosion performance of ZrO₂ coating in nuclear water chemistry is relatively scarce, and existing reports failed to provide an in-depth explanation for the failure causes of ZrO₂ coating. Herein, a detailed corrosion process of ZrO₂ coating in lithiated water at 360 °C and 18.5 MPa was proposed based on experimental research and molecular dynamics simulation. Lithiated water with different LiOH solutions in the present work was deaerated and had a dissolved oxygen concentration of < 10 ppb. The concentration of Li (as LiOH) was determined to be 2.3 ppm, 70 ppm, and 500 ppm, respectively. Corrosion tests were conducted in a static autoclave. Modeling and corresponding calculations were operated on Materials Studio software. The calculation of adsorption energy and dynamics parameters were undertaken by the Energy task and Dynamics task of the Forcite module, respectively. The protective effect and failure mechanism of ZrO₂ coating on Zry-4 under varied LiOH concentrations was further revealed by comparison with the coating corrosion performance in pure water (namely 0 ppm Li). ZrO₂ coating provided a favorable corrosion protection with the occurrence of localized corrosion at low LiOH concentrations. Factors influencing corrosion resistance mainly include pitting corrosion extension, enhanced Li+ permeation, short-circuit diffusion of O²⁻ and ZrO₂ phase transformation. In highly-concentrated LiOH solutions, intergranular corrosion, internal oxidation, and perforation resulted in coating failure. Zr ions were released to coating surface to form flocculent ZrO₂ and ZrO₂ clusters due to the strong diffusion and dissolution tendency of α-Zr in the Zry-4 substrate. Considering that primary water of Pressurized Water Reactors usually includes 2.3 ppm Li, the stability of ZrO₂ make itself a candidate fuel cladding coating material. Under unfavorable conditions with high Li concentrations, more boric acid should be added to alleviate caustic corrosion of ZrO₂ coating once it is used. This work can provide some references to understand the service behavior of nuclear coatings under variable water chemistry conditions and promote the in-pile application of ZrO₂ coating.

Keywords: ZrO₂ coating, Zry-4, corrosion behavior, failure mechanism, LiOH concentration

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855 On a Theoretical Framework for Language Learning Apps Evaluation

Authors: Juan Manuel Real-Espinosa

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This paper addresses the first step to evaluate language learning apps: what theoretical framework to adopt when designing the app evaluation framework. The answer is not just one since there are several options that could be proposed. However, the question to be clarified is to what extent the learning design of apps is based on a specific learning approach, or on the contrary, on a fusion of elements from several theoretical proposals and paradigms, such as m-learning, mobile assisted language learning, and a number of theories about language acquisition. The present study suggests that the reality is closer to the second assumption. This implies that the theoretical framework against which the learning design of the apps should be evaluated must also be a hybrid theoretical framework, which integrates evaluation criteria from the different theories involved in language learning through mobile applications.

Keywords: mobile-assisted language learning, action-oriented approach, apps evaluation, post-method pedagogy, second language acquisition

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854 The Science of Successful Intimate Relationship in China: A Discourse Analytic Examination of Sex and Relationships Advice in Ayawawa’s Book

Authors: Hanlei Yang

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As a kind of popular culture in modern China, advice book on intimate relationship is turning into an important and controversial site with conflicts among neoliberalism, authoritative socialism, market-oriented principles, the science of successful sex and relationship, cosmopolitan notions of nuclear families, and the revitalization of Confucian conservatism and patriarchy. Accelerated modernization and marketization has contributed to great changes in China’s culture and social relations, which accordingly reconceptualizes and reconstructs family structures and moral ethics, particularly urban middle-class nuclear families. To comprehend the meaning of advice book fad in moral and social order, this research proposes to (i) understand the implication of Ayawawa through discourse analysis and how she mobilizes rhetorical devices and cultural resources to present a persuasive and scientific method of managing intimate relationship, (ii) examine the critical role of neoliberalism, post-feminism, and Confucian patriarchy assumed by Ayawawa in her books, (iii) explore how Ayawawa and her fans engage in establishing a model of intimate relationship and sexual subjectivity ordered by neoliberalism, class identity and authoritative socialism. Finally, this research argues that such new fad of a cultural phenomenon is gradually completed in the process of cooperation and negotiation of the state, commercial institutions, and intellectual elite agents. It helps to further learn about (i) the routine life under the influence of neoliberalism and modern hegemony, (ii) the perplexing relationship between China's indigenous cultural forms, global socio-economic and cultural influences in the late modern era.

Keywords: cultural study, intimate relationship, culture sociology, gender study

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853 Industrial Rock Characterization using Nuclear Magnetic Resonance (NMR): A Case Study of Ewekoro Quarry

Authors: Olawale Babatunde Olatinsu, Deborah Oluwaseun Olorode

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Industrial rocks were collected from a quarry site at Ewekoro in south-western Nigeria and analysed using Nuclear Magnetic Resonance (NMR) technique. NMR measurement was conducted on the samples in partial water-saturated and full brine-saturated conditions. Raw NMR data were analysed with the aid of T2 curves and T2 spectra generated by inversion of raw NMR data using conventional regularized least-squares inversion routine. Results show that NMR transverse relaxation (T2) signatures fairly adequately distinguish between the rock types. Similar T2 curve trend and rates at partial saturation suggests that the relaxation is mainly due to adsorption of water on micropores of similar sizes while T2 curves at full saturation depict relaxation decay rate as: 1/T2(shale)>1/ T2(glauconite)>1/ T2(limestone) and 1/T2(sandstone). NMR T2 distributions at full brine-saturation show: unimodal distribution in shale; bimodal distribution in sandstone and glauconite; and trimodal distribution in limestone. Full saturation T2 distributions revealed the presence of well-developed and more abundant micropores in all the samples with T2 in the range, 402-504 μs. Mesopores with amplitudes much lower than those of micropores are present in limestone, sandstone and glauconite with T2 range: 8.45-26.10 ms, 6.02-10.55 ms, and 9.45-13.26 ms respectively. Very low amplitude macropores of T2 values, 90.26-312.16 ms, are only recognizable in limestone samples. Samples with multiple peaks showed well-connected pore systems with sandstone having the highest degree of connectivity. The difference in T2 curves and distributions for the rocks at full saturation can be utilised as a potent diagnostic tool for discrimination of these rock types found at Ewekoro.

Keywords: Ewekoro, NMR techniques, industrial rocks, characterization, relaxation

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852 Simulation Of A Renal Phantom Using the MAG 3

Authors: Ati Moncef

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We describe in this paper the results of a phantom of dynamics renal with MAG3. Our phantom consisted of (tow shaped of kidneys, 1 liver). These phantoms were scanned with static and dynamic protocols and compared with clinical data. in a normal conditions we use our phantoms it's possible to acquire a renal images when we can be compared with clinical scintigraphy. In conclusion, Renal phantom also can use in the quality control of a renal scintigraphy.

Keywords: Renal scintigraphy, MAG3, Nuclear medicine, Gamma Camera.

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851 Effect of Thermal Aging on Low Cycle Fatigue of Alloy 690

Authors: Kushal Gowda Jayaram, Joseph Huret, Jonathan Quibel, Walter-John Chitty, Gilbert Henaff

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Thermal aging is one of the concerns for the long-term operation of nuclear power plants. Indeed, components in the primary circuit undergo thermal aging while exposed to the chemically active environment of Pressurized Water Reactors (PWRs) over time. Among the materials used in the reactor components, Alloy 690 can be found in some critical components for nuclear safety. Despite its importance, research on the effect of thermal aging on the microstructural changes and low cycle fatigue (LCF) behavior of Alloy 690 remains limited. This study aims to assess the impact of thermal aging on the fatigue life of Alloy 690. The as-received sample underwent aging at 420°C for 4000 hours, representing the equivalent aging of 60 years in reactor working conditions. First, the characterization of the area and density of intergranular and intragranular precipitates was performed to understand the microstructural changes in the aged specimen. Then, low cycle fatigue tests were conducted on the as received and aged samples at varying strain amplitudes. To investigate the influence of thermal aging on the fatigue behavior of Alloy 690, fracture surfaces were analyzed to estimate fatigue crack growth rates based on striation spacing measurements. Additionally, the axially cut fractured samples have undergone analysis using Electron Backscatter Diffraction (EBSD) to understand the effect of aging on strain localization near the crack path. Results indicate that while the characterization of the area and density of intergranular precipitates in the aged specimen (for 2000 hours, approximately 30 years) showed no significant changes, there was a slight increase in the area and density of intragranular precipitates under the same conditions.

Keywords: alloy 690, thermal aging, low cycle fatigue, precipitates

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850 Functional and Efficient Query Interpreters: Principle, Application and Performances’ Comparison

Authors: Laurent Thiry, Michel Hassenforder

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This paper presents a general approach to implement efficient queries’ interpreters in a functional programming language. Indeed, most of the standard tools actually available use an imperative and/or object-oriented language for the implementation (e.g. Java for Jena-Fuseki) but other paradigms are possible with, maybe, better performances. To proceed, the paper first explains how to model data structures and queries in a functional point of view. Then, it proposes a general methodology to get performances (i.e. number of computation steps to answer a query) then it explains how to integrate some optimization techniques (short-cut fusion and, more important, data transformations). It then compares the functional server proposed to a standard tool (Fuseki) demonstrating that the first one can be twice to ten times faster to answer queries.

Keywords: data transformation, functional programming, information server, optimization

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849 Stress Corrosion Crack Identification with Direct Assessment Method in Pipeline Downstream from a Compressor Station

Authors: H. Gholami, M. Jalali Azizpour

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Stress Corrosion Crack (SCC) in pipeline is a type of environmentally assisted cracking (EAC), since its discovery in 1965 as a possible cause of failure in pipeline, SCC has caused, on average, one of two failures per year in the U.S, According to the NACE SCC DA a pipe line segment is considered susceptible to SCC if all of the following factors are met: The operating stress exceeds 60% of specified minimum yield strength (SMYS), the operating temperature exceeds 38°C, the segment is less than 32 km downstream from a compressor station, the age of the pipeline is greater than 10 years and the coating type is other than Fusion Bonded Epoxy(FBE). In this paper as a practical experience in NISOC, Direct Assessment (DA) Method is used for identification SCC defect in unpiggable pipeline located downstream of compressor station.

Keywords: stress corrosion crack, direct assessment, disbondment, transgranular SCC, compressor station

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848 'CardioCare': A Cutting-Edge Fusion of IoT and Machine Learning to Bridge the Gap in Cardiovascular Risk Management

Authors: Arpit Patil, Atharav Bhagwat, Rajas Bhope, Pramod Bide

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This research integrates IoT and ML to predict heart failure risks, utilizing the Framingham dataset. IoT devices gather real-time physiological data, focusing on heart rate dynamics, while ML, specifically Random Forest, predicts heart failure. Rigorous feature selection enhances accuracy, achieving over 90% prediction rate. This amalgamation marks a transformative step in proactive healthcare, highlighting early detection's critical role in cardiovascular risk mitigation. Challenges persist, necessitating continual refinement for improved predictive capabilities.

Keywords: cardiovascular diseases, internet of things, machine learning, cardiac risk assessment, heart failure prediction, early detection, cardio data analysis

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847 Comprehensive Risk Analysis of Decommissioning Activities with Multifaceted Hazard Factors

Authors: Hyeon-Kyo Lim, Hyunjung Kim, Kune-Woo Lee

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Decommissioning process of nuclear facilities can be said to consist of a sequence of problem solving activities, partly because there may exist working environments contaminated by radiological exposure, and partly because there may also exist industrial hazards such as fire, explosions, toxic materials, and electrical and physical hazards. As for an individual hazard factor, risk assessment techniques are getting known to industrial workers with advance of safety technology, but the way how to integrate those results is not. Furthermore, there are few workers who experienced decommissioning operations a lot in the past. Therefore, not a few countries in the world have been trying to develop appropriate counter techniques in order to guarantee safety and efficiency of the process. In spite of that, there still exists neither domestic nor international standard since nuclear facilities are too diverse and unique. In the consequence, it is quite inevitable to imagine and assess the whole risk in the situation anticipated one by one. This paper aimed to find out an appropriate technique to integrate individual risk assessment results from the viewpoint of experts. Thus, on one hand the whole risk assessment activity for decommissioning operations was modeled as a sequence of individual risk assessment steps, and on the other, a hierarchical risk structure was developed. Then, risk assessment procedure that can elicit individual hazard factors one by one were introduced with reference to the standard operation procedure (SOP) and hierarchical task analysis (HTA). With an assumption of quantification and normalization of individual risks, a technique to estimate relative weight factors was tried by using the conventional Analytic Hierarchical Process (AHP) and its result was reviewed with reference to judgment of experts. Besides, taking the ambiguity of human judgment into consideration, debates based upon fuzzy inference was added with a mathematical case study.

Keywords: decommissioning, risk assessment, analytic hierarchical process (AHP), fuzzy inference

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846 The Death of God: Between Nietzsche and Muhammad Iqbal

Authors: Maruf Hasan

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This article will investigate how Muhammad Iqbal integrated key aspects of Nietzsche's philosophy into Islamic spirituality. At the same time, it sees how Iqbal developed a Tawhidic paradigm which differed from Nietzsche's atheism. The literary study of Nietzsche and Iqbal's texts, as well as their influence on Western and Muslim discourse, are used in this study as part of a qualitative research methodology. The result is that Iqbal accepted most of Nietzsche's ideas, while affirming Islamic Aqida. The article's conclusion is that, so long as a Tawhidic paradigm is upheld, there are no restrictions on the integration of knowledge. Iqbal's writings serve as a template for the fusion of Western and Islamic thought, presenting a solution to the apparent incompatibility of these two sets of beliefs. In order to deepen our awareness of the world and foster respect and understanding among cultures and religions, this research emphasizes the value of connecting with other perspectives.

Keywords: Nietzsche, Muhammad Iqbal, post-Islamism, post-Islamism interpretative approach

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845 The Role of Cultural Expectations in Emotion Regulation among Nepali Adolescents

Authors: Martha Berg, Megan Ramaiya, Andi Schmidt, Susanna Sharma, Brandon Kohrt

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Nepali adolescents report tension and negative emotion due to perceived expectations of both academic and social achievement. These societal goals, which are internalized through early-life socialization, drive the development of self-regulatory processes such as emotion regulation. Emotion dysregulation is linked with adverse psychological outcomes such as depression, self-harm, and suicide, which are public health concerns for organizations working with Nepali adolescents. This study examined the relation among socialization, internalized cultural goals, and emotion regulation to inform interventions for reducing depression and suicide in this population. Participants included 102 students in grades 7 through 9 in a post-earthquake school setting in rural Kathmandu valley. All participants completed a tablet-based battery of quantitative measures, comprising transculturally adapted assessments of emotion regulation, depression, and self-harm/suicide ideation and behavior. Qualitative measures included two focus groups and semi-structured interviews with 22 students and 3 parents. A notable proportion of the sample reported depression symptoms in the past 2 weeks (68%), lifetime self-harm ideation (28%), and lifetime suicide attempts (13%). Students who lived with their nuclear family reported lower levels of difficulty than those who lived with more distant relatives (z=2.16, p=.03), which suggests a link between family environment and adolescent emotion regulation, potentially mediated by socialization and internalization of cultural goals. These findings call for further research into the aspects of nuclear versus extended family environments that shape the development of emotion regulation.

Keywords: adolescent mental health, emotion regulation, Nepal, socialization

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844 Friction Stir Welding of Al-Mg-Mn Aluminum Alloy Plates: A Review

Authors: K. Subbaiah, C. V. Jayakumar

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Friction stir welding is a solid state welding process. Friction stir welding process eliminates the defects found in fusion welding processes. It is environmentally friend process. 5000 and 6000 series aluminum alloys are widely used in the transportation industries. The Al-Mg-Mn (5000) and Al-Mg-Si (6000) alloys are preferably offer best combination of use in Marine construction. The medium strength and high corrosion resistant 5000 series alloys are the aluminum alloys, which are found maximum utility in the world. In this review, the tool pin profile, process parameters such as hardness, yield strength and tensile strength, and microstructural evolution of friction stir welding of Al-Mg-Mn alloys (5000 Series) have been discussed.

Keywords: Al-Mg-Mn alloys, friction stir welding, tool pin profile, microstructure and mechanical properties

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843 Genotoxic and Cytotoxic Effects of Salvia officinals Extracts on Rat Bone Marrow

Authors: Mohammed A. Alshehri

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Salvia officinalis is an aromatic plant member of the mint (Labiatae) family. It is popular kitchen herb. Not surprise to find that the name of this herb related to cure, in Latin language Salvia means to cure where officinalis means medicinal which answer why the sage has a top place in the list of medicinal plants. The aim of the present study was to assess the genetic damage and cytological changes caused by exposure of the test organism (Rattusrattus) to Salvia officinals. For this purpose, adult female rats, weighing 200–250 g, were used as donors. A total of 36 adult Wister male rats were randomly assigned to five groups: the experimental groups (rats were intraperitonealy injected with Salvia officinalis pure extract at (0.1, 0.2, 0.5, 0.1mg/kg body weight, the same dose was administered once a day. Control group (rats were injected intraperitonealy physiological saline. And positive control were injected with Cyclophosphamide. On the 21st days following Salvia officinalis pure extract exposure, rats were sacrificed, and samples of bone marrow were collected. Following that, we performed a micronuclei (MN) test using MNNCE (Micro-nucleated normocromatic erythrocytes) and MNPCE (Micronucleated polychromatic erythrocytes), NDI (Nuclear division index), and cytological parameters using NDCI (nuclear division cytotoxicity index), necrotic, and apoptotic cells in rat's bone marrow samples. Results showed that there was a no significant increase in the frequency of micro-nucleatedas well as in cytological parameters in bone marrow cells. In light of these results, if Salvia officinalis pure extract may considered to be safe from the stand point of genotoxicity and cytotoxicity effects.

Keywords: Salvia officinalis, micronucleus, NDI, NDCI, toxicity, chromosomal aberrations

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842 The Strength and Metallography of a Bimetallic Friction Stir Bonded Joint between AA6061 and High Hardness Steel

Authors: Richard E. Miller

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12.7-mm thick plates of 6061-T6511 aluminum alloy and high hardness steel (528 HV) were successfully joined by a friction stir bonding process using a tungsten-rhenium stir tool. Process parameter variation experiments, which included tool design geometry, plunge and traverse rates, tool offset, spindle tilt, and rotation speed, were conducted to develop a parameter set which yielded a defect free joint. Laboratory tensile tests exhibited yield stresses which exceed the strengths of comparable AA6061-to-AA6061 fusion and friction stir weld joints. Scanning electron microscopy and energy dispersive X-ray spectroscopy analysis also show atomic diffusion at the material interface region.

Keywords: dissimilar materials, friction stir, welding, materials science

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841 Wearable Music: Generation of Costumes from Music and Generative Art and Wearing Them by 3-Way Projectors

Authors: Noriki Amano

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The final goal of this study is to create another way in which people enjoy music through the performance of 'Wearable Music'. Concretely speaking, we generate colorful costumes in real- time from music and to realize their dressing by projecting them to a person. For this purpose, we propose three methods in this study. First, a method of giving color to music in a three-dimensionally way. Second, a method of generating images of costumes from music. Third, a method of wearing the images of music. In particular, this study stands out from other related work in that we generate images of unique costumes from music and realize to wear them. In this study, we use the technique of generative arts to generate images of unique costumes and project the images to the fog generated around a person from 3-way using projectors. From this study, we can get how to enjoy music as 'wearable'. Furthermore, we are also able to have the prospect of unconventional entertainment based on the fusion between music and costumes.

Keywords: entertainment computing, costumes, music, generative programming

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840 Engineering Thermal-Hydraulic Simulator Based on Complex Simulation Suite “Virtual Unit of Nuclear Power Plant”

Authors: Evgeny Obraztsov, Ilya Kremnev, Vitaly Sokolov, Maksim Gavrilov, Evgeny Tretyakov, Vladimir Kukhtevich, Vladimir Bezlepkin

Abstract:

Over the last decade, a specific set of connected software tools and calculation codes has been gradually developed. It allows simulating I&C systems, thermal-hydraulic, neutron-physical and electrical processes in elements and systems at the Unit of NPP (initially with WWER (pressurized water reactor)). In 2012 it was called a complex simulation suite “Virtual Unit of NPP” (or CSS “VEB” for short). Proper application of this complex tool should result in a complex coupled mathematical computational model. And for a specific design of NPP, it is called the Virtual Power Unit (or VPU for short). VPU can be used for comprehensive modelling of a power unit operation, checking operator's functions on a virtual main control room, and modelling complicated scenarios for normal modes and accidents. In addition, CSS “VEB” contains a combination of thermal hydraulic codes: the best-estimate (two-liquid) calculation codes KORSAR and CORTES and a homogenous calculation code TPP. So to analyze a specific technological system one can build thermal-hydraulic simulation models with different detalization levels up to a nodalization scheme with real geometry. And the result at some points is similar to the notion “engineering/testing simulator” described by the European utility requirements (EUR) for LWR nuclear power plants. The paper is dedicated to description of the tools mentioned above and an example of the application of the engineering thermal-hydraulic simulator in analysis of the boron acid concentration in the primary coolant (changed by the make-up and boron control system).

Keywords: best-estimate code, complex simulation suite, engineering simulator, power plant, thermal hydraulic, VEB, virtual power unit

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839 Introduction of PMMA-Tag to VHH for Improving Recovery and Immobilization Rate of VHHS

Authors: Bongmun Kang, Kagnari Yamakawa, Yoshihisa Hagihara, Yuji Ito, Michimasa Kishimoto, Yoichi Kumada

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The PMMA-tag was genetically fused with the C-terminal region of VHH molecules. This antibody, VHH, is known as a single-chain domain, which is devoid of light chains. The PMMA-tag, which could affect the isoelectric point (pI) changeable with a charge of amino acid in VHHs were closely related to the solubility of VHH molecules during refolding. The genetic fusion of PMMA-tag to C-terminal region of VHHs significantly affects the recovery of their soluble protein during refolding by 50 mM TAPS at pH 8.5. It could be refolded with a recovery of more than 95% by dialysis at pH 8.5. A marked difference in the antigen-binding activities in the adsorption state was significantly high in VHH-PM compared to the wild type of VHH. There are approximately 8-fold differences in the antigen-binding activities in the adsorption state between VHH-PM and VHH.

Keywords: VHH, PMMA-tag, isoelectric point, pH, Solubility, refolding, immobilization, ELISA

Procedia PDF Downloads 419